Techniques including molecular display, cell lineage tracing, and use of Xenopus embryos as a functional assay system will be employed to characterize maternally-inherited factors that determine fates of cells that contribute to the developing central nervous system and other dorsal axial structures in these embryo. The crucial roles such factors are likely to play in neural development suggest that they will be conserved in other vertebrates, and thus hold out a good chance of helping us understand and prevent defects in neural development in humans.